Gray cloth and process of dyeing same.



UNITED STATES PATENT EOrrrcn.

TVI LHELM ELBERS, OF HAGEN, GERMANY, ASSIGNOR TO THE BADISCHE ANILIN AND SODA FABRIK, OF LUDWIGSHAFEN, GERMANY.

GRAY CLOTH ANE Pfifi 6F DYTEING SAME.

SPECIFICATION forming part of Letters Patent No. 650,752, dated May 29, 1900.

' Application filed June 15, 18981 $ciia1 lie-683 #194. (Specimens) To all whom it my camera:

Be it known that LWILHELM EL'EERs, doctor of philosophy, a subject of the King of Prussia,German Emperor, residing at Hagen,

Westphalia, in the Kingdom of Prussia and ture-namely, a gray-indigo coloring-matter in combination with textile fiberwhich possesses to a high degree the property of fastness against the action of light, thus rendering it possible to use fabrics of a gray shade, even in cases, such as furniture coverings, where fastness to light is an essential. My new coloring-matter in this combination possesses the same fastness against acids and chlorid of lime and gives the same reactions as indigo-blue. It can be discharged with chromic acid and other colors printed on, so that goods with various effects on a gray ground are obtained.

My invention opens up a new field of utility to the coloring-matter indigo, which can, with its assistance, be utilized for the manufacture of gray goods, whereas hitherto it by itself could only be used for obtaining blue shades.

All hitherto-known processes for fixing indigo, except, of course, the sulfoacids of indigo on the different textile fibers, are based upon the fact that the insoluble indigo-blue is first reduced to soluble indigo-white by means of reducing agents. Then the textile fiber is impregnated with the indigo-white in a suitable manner by dyeing or printing, and then the indigo-white is on the fiber again converted into indigo-blue by oxidation, preferably by means of the oxygen of the air.

' My invention consists in the production of a gray-indigo dyestuff in combination with textile fiber, and I use no reduction process. The process for this production consists, substantially, in mixing finely ground or divided indigo with preferably comparatively large quantities of oils or oil derivatives, thickening it with suitable substances, and then printing it on or impregnating with it the textile fiber, then subjecting the tissue to the action of steam for about one or two hours,

washing and soaping. in order to iix the color completely, the action of steam must continue for a long time, but it is not absolutely necessary to use high-pressure steam, only of course the operation takes correspondingly longer when low-pressure steam is employed. Hereby is to be observed that steaming at too high a pressure has an injurious effect on woolen and silk flbers,wherefore in these cases the steaming operations must be made longer and the pressure lower. The fabric thus obtained is of a good uniform blue-gray color. The addition of a compara tively-large quantity of the oils as mentionedas, for instance, olive-oil, sesameoil, castor-oil, fat, and the like'is essential to the complete success of the process, as, although the new gray coloring-matter in combination with the fiber can be obtained without it quite as fast, still the goods are coloring-matter in combination with the fiber can be considerably increased by subjecting the fabric printed or dyed-that is, padded with indigoafter it has been steamed and freed from thickening or gum to a second steaming for a considerable time under a comparatively-high pressure. The essential point is to remove by washing and treating with malt all traces of gum or thickening from the fabric before subjecting it to this second steaming operation. A much longer or he quently-repeated steaming of the unwashed fabric has far less efiect than a steaming repeated after the fabric has been completely deprived of gum or thickening (by washing and treating with malt) between the two It is also important to steaming operations. effect the second steaming operation at a comparatively-high pressure. This second steaming operation is preferably to be used for obtaining the gray-indigo coloring-matter in combination with the cotton fiber, and it is especially important for fabrics which are required to have great fastness or permanency under friction and soap-as, for instance, in washing fabrics for dresses.)

The following examples will serve to further illustrate the nature of my invention and the manner in which it can best be carried into practical effect.

atmosphere for aboutthree to four hours,

whereby the new gray to blue-gray coloringmatter is generated in combination with the fiber. Then the gum is removed and the fabric treated with soap.

Example 2Production of the new gray coloring-matter in combination with cotton fiber by a padding or dyeing process.- To obtain the gray color in combination with cotton bya dyeing orpadding process, mix one hundred (100) parts of finely-ground twenty-per-ccnt. (20%) indigo paste, two hundred (200) parts of ricinoleate of soda, seven hundred (700) parts of tragacanth water. The fabric to be dyed is impregnated or padded with this dye with the aid of a hot flue, then subjected for about two hours to the action of steam at about 0.7 to 1.0 atmosphere pressure, whereby the new gray coloring-matter is developed on the fiber. lhen the fabric is malted and soaped.

Example 3-P7O(llt0tt07't of the new gray colo'ringmatter in combination with wool or sillc.\Voolen or silk fabric prepared for printing in the usual way is printed upon with the following dye mixture: about nine hundred and sixty to nine hundred (960 to 900) parts of thickening material, about twenty to fifty (20 to 50) parts of indigo, and about twenty to fifty (20 to 50) parts of olive-oil. After the printing the fabric is steamed for two hours without pressure, whereby the new coloring-matter is developed. The fabric is then well washed and finished.

Example J;Pro(luction of the new gray coloring-matter in combination with cotton arlopting a second steaming opcration.-The fabric prepared for printing in the usual way is printed on with a color mixture constituted, say, as follows: about nine hundred and sixty to nine hundred (960 to 900) parts of thickening material, about twenty to fifty (20 to 50) parts indigo paste, (containing twenty per cent. (20%) indigo,) and about twenty to fifty (20 to 50) parts of olive-oil. After the printing the fabric is steamed for about two hours at 0.1 atmosphere pressure, then washed, treated with malt, washed, and dried. It is then steamed again for about one hour and a half at, say, 0.7 to 1.0 atmosphere pressure and finished in the usual manner.

My new gray-indigo coloring-matter in combination with the fibers possesses the fo1lowing characteristic properties: it can be drawn off the fabric in the same manner as indigoblue by heating a test portion with a solventas, for instance, analin, glacial acetic acid, chloroform, and the likeand also by means of reducing agents-as, for instance, zinc-dust and caustic soda, hydrosulfite, and the like-and the solutions so obtained contain ordinary indigo or indigo-white. By rubbing the fabrics containing my new gray coloring-matter combined with the fiber with a cloth the place rubbed shows a blue-indigo shade, not only on cotton, but also on wool and silk. When the gray indigo is'prepared with a solution of grapesugar and then printed with thickened caustic soda and shortly steamed, it is also converted into indigo-blue on the printed places, the graycoloring-matter being apparently reconverted in ordinary blue indigo. By printing potassium chromate on the gray indigo and drawing the tissue through a sulfuric and oxalic acid bath then the gray indigo on the printed places becomes oxidized and destroyed in a manner similar to indigo blue, the gray color becoming discharged to white. \Vhen suitable yellow, red, or green colors and albumen are added to the potassium chromate, colored effects can be produced on the gray grou nd in the same way as hereto on an indigo-blue ground.

Save in combination with the fiber as herein described no means are known for the production of the new gray-indigo coloring-matter.

Now what I claim is 1. As a new article of manufacture a graycolored fabric composed of textile fibrous material and indigo and having a high degree of fastness to light, acids and chloride of lime (bleaching powder) and which can be removed from the fiber by solvents or reducing mixtures as specified, yielding solutions of indigo or indigo-white and which by rubbing with a cloth or steaming with grape-sugar and caustic soda assumes an indigo-blue color and which can be oxidized and destroyed by acid oxidation, all substantially as described.

2. A process for the production of gray-indigo coloring-matter in combination with the fiber consisting in printing a paste of finelydivided indigo, a suitable thickening and a quantity of oil on the fiber and steaming and working up all substantially as hereinbefore described.

3. A process for the production of gray-indigo coloring-matters in combination with the fiber consisting in printing a paste of finelydivided indigo, a suitable thickening and a quantity of oil on the fiber and steaming, then freeing from thickening by washing and treating with malt, drying and subjecting to a second steaming operation all substantially as hereinbefore described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

\VILHELM ELBERS.

Witnesses:

R. E. Jana, OTTO KONIG. 

